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Using the ScientificNotationThreshold option inside NumberForm causes erroneous behavior and generates a mystifying error message when used inside Dynamic.

For example, running

With[{x = N[-\[Pi] 10^4]},
 Print[{
   NumberForm[x],
   NumberForm[x, ScientificNotationThreshold -> {-3, 3}]
   }];
 Grid[{{
    Dynamic[NumberForm[x], (x = #) &],
    Dynamic[
     NumberForm[x, 
      ScientificNotationThreshold -> {-3, 3}], (x = #) &]},
   {InputField[
     Dynamic[Style[NumberForm[x], 
       ShowStringCharacters -> False], (x = #) &], FieldSize -> 5, 
     Alignment -> Right],
    InputField[
     Dynamic[Style[
       NumberForm[x, ScientificNotationThreshold -> {-3, 3}], 
       ShowStringCharacters -> False], (x = #) &], FieldSize -> 5, 
     Alignment -> Right]}
   }]
 ]

produces this output

enter image description here

accompanied by the twice repeated error message

NumberForm::expons: The value ScientificNotationThreshold of the option {-3,3} should be a list of two values. Each can be a machine integer or +/- Infinity.

In the example, NumberForm is invoked three times

  1. Not inside Dynamic
  2. Inside Dynamic, and
  3. Inside an InputField that contains a Dynamic argument

and each one is done two different ways, once WITHOUT and once WITH the ScientificNotationThreshold option explicitly set.

The error occurs only when I try to explicitly set the ScientificNotationThreshold option inside Dynamic.

Even the statement of the error seems slightly backward.

What's going on here?

Seems like a bug in Mathematica to me.

Is there a simple way to make this work the way it's supposed to?

Note: I included the two cases that use InputField merely to show the type of code I actually intend to use and why Dynamic is necessary for my purposes.

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  • 1
    $\begingroup$ Pink boxes no longer appear in 13.1. $\endgroup$
    – QuantumDot
    Oct 1, 2022 at 19:10

1 Answer 1

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This bug still persists in Mathematica 12.3.

Workaround

Define

ToRawBoxesQuiet[value_] := Quiet[RawBoxes[ToBoxes[value]]]

and use the function before calling Dynamic:

Dynamic[ToRawBoxesQuiet[...]]

or Manipulate

Manipulate[
  ToRawBoxesQuiet[...],
  ...
]

How I found the workaround

I used

Dynamic[NumberForm[1, ScientificNotationThreshold -> {-4, 4}]]

as an example.

In the stack trace of the error there is the line

MakeBoxes[NumberForm[1, ScientificNotationThreshold -> {-4, 4}], StandardForm]

so it seems like a bug of MakeBoxes and NumberForm. So I tried to manually create the boxes (using ToBoxes) and use Quiet to suppress the error message.

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